Whats this washer doing in my trans pan

[dodge freak 2]

My tranny is the 904 with a cheetah manual valve body. About 5 years old, changed the fluid 2007 but it gets store during the winter.

Well when cold-semi warm I felt it sipping from a dead stop while in 3rd gear. Went back and check the fluid level, was fine. So I adjusted the kickdown band. Felt fine afterward  in 3rd but then in 1st gear it slip again but I floored it and it ran fine and was OK for 20 mins in all type of driving. Had dinner, ran out and I felt it slip in 2nd from a dead stop again,  seem to shake this time. Once again when warmed up was great.

I pulled the pan off, not too bad inside, some grit-the size of a US half dollar coin. Filter had about the same...but then when cleaning the pan I found a thin washer with a slot, hope you can tell by the pictures...all valve body bolts seem tight, just a got a slight turn on a few..very slight.

[tactransman]

It looks like it is off the dip stick at the top where the seal is under the cap.

[dodge freak 2]

  You just might be right...my dipstick cap is loose on the stick but seals fine once in....I do know how to push down on the cap when I check the level...been that way "forever", lol.

I would have took it to my trans guy but hes 30 min drive away and close al weekend. Did phone him before dinner and he said maybe a valve was sticking, don't worry about it. But then when I felt it slip again this time in 2nd gear from a dead stop, I thought I should put a new filter and check to see if the valve body is tight...if it acts up anymore I guess I take it over there.

Thanks!